<?php

    /**
     * PHPExcel_CachedObjectStorage_CacheBase
     * Copyright (c) 2006 - 2015 PHPExcel
     * This library is free software; you can redistribute it and/or
     * modify it under the terms of the GNU Lesser General Public
     * License as published by the Free Software Foundation; either
     * version 2.1 of the License, or (at your option) any later version.
     * This library is distributed in the hope that it will be useful,
     * but WITHOUT ANY WARRANTY; without even the implied warranty of
     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     * Lesser General Public License for more details.
     * You should have received a copy of the GNU Lesser General Public
     * License along with this library; if not, write to the Free Software
     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
     * @category   PHPExcel
     * @package    PHPExcel_CachedObjectStorage
     * @copyright  Copyright (c) 2006 - 2015 PHPExcel (http://www.codeplex.com/PHPExcel)
     * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
     * @version    ##VERSION##, ##DATE##
     */
    abstract class PHPExcel_CachedObjectStorage_CacheBase {
        /**
         * Parent worksheet
         * @var PHPExcel_Worksheet
         */
        protected $parent;
        /**
         * The currently active Cell
         * @var PHPExcel_Cell
         */
        protected $currentObject = null;
        /**
         * Coordinate address of the currently active Cell
         * @var string
         */
        protected $currentObjectID = null;
        /**
         * Flag indicating whether the currently active Cell requires saving
         * @var boolean
         */
        protected $currentCellIsDirty = true;
        /**
         * An array of cells or cell pointers for the worksheet cells held in this cache,
         *        and indexed by their coordinate address within the worksheet
         * @var array of mixed
         */
        protected $cellCache = [];

        /**
         * Initialise this new cell collection
         * @param    PHPExcel_Worksheet $parent The worksheet for this cell collection
         */
        public function __construct(PHPExcel_Worksheet $parent) {
            //    Set our parent worksheet.
            //    This is maintained within the cache controller to facilitate re-attaching it to PHPExcel_Cell objects when
            //        they are woken from a serialized state
            $this->parent = $parent;
        }

        /**
         * Identify whether the caching method is currently available
         * Some methods are dependent on the availability of certain extensions being enabled in the PHP build
         * @return    boolean
         */
        public static function cacheMethodIsAvailable() {
            return true;
        }

        /**
         * Return the parent worksheet for this cell collection
         * @return    PHPExcel_Worksheet
         */
        public function getParent() {
            return $this->parent;
        }

        /**
         * Is a value set in the current PHPExcel_CachedObjectStorage_ICache for an indexed cell?
         * @param    string $pCoord Coordinate address of the cell to check
         * @return    boolean
         */
        public function isDataSet($pCoord) {
            if ($pCoord === $this->currentObjectID) {
                return true;
            }
            //    Check if the requested entry exists in the cache
            return isset($this->cellCache[$pCoord]);
        }

        /**
         * Move a cell object from one address to another
         * @param    string $fromAddress Current address of the cell to move
         * @param    string $toAddress   Destination address of the cell to move
         * @return    boolean
         */
        public function moveCell($fromAddress, $toAddress) {
            if ($fromAddress === $this->currentObjectID) {
                $this->currentObjectID = $toAddress;
            }
            $this->currentCellIsDirty = true;
            if (isset($this->cellCache[$fromAddress])) {
                $this->cellCache[$toAddress] = &$this->cellCache[$fromAddress];
                unset($this->cellCache[$fromAddress]);
            }
            return true;
        }

        /**
         * Add or Update a cell in cache
         * @param    PHPExcel_Cell $cell Cell to update
         * @return    PHPExcel_Cell
         * @throws    PHPExcel_Exception
         */
        public function updateCacheData(PHPExcel_Cell $cell) {
            return $this->addCacheData($cell->getCoordinate(), $cell);
        }

        /**
         * Sort the list of all cell addresses currently held in cache by row and column
         * @return    string[]
         */
        public function getSortedCellList() {
            $sortKeys = [];
            foreach ($this->getCellList() as $coord) {
                sscanf($coord, '%[A-Z]%d', $column, $row);
                $sortKeys[sprintf('%09d%3s', $row, $column)] = $coord;
            }
            ksort($sortKeys);
            return array_values($sortKeys);
        }

        /**
         * Get a list of all cell addresses currently held in cache
         * @return    string[]
         */
        public function getCellList() {
            return array_keys($this->cellCache);
        }

        /**
         * Return the cell address of the currently active cell object
         * @return    string
         */
        public function getCurrentAddress() {
            return $this->currentObjectID;
        }

        /**
         * Return the column address of the currently active cell object
         * @return    string
         */
        public function getCurrentColumn() {
            sscanf($this->currentObjectID, '%[A-Z]%d', $column, $row);
            return $column;
        }

        /**
         * Return the row address of the currently active cell object
         * @return    integer
         */
        public function getCurrentRow() {
            sscanf($this->currentObjectID, '%[A-Z]%d', $column, $row);
            return (integer)$row;
        }

        /**
         * Get highest worksheet column
         * @param   string $row                Return the highest column for the specified row,
         *                                     or the highest column of any row if no row number is passed
         * @return  string     Highest column name
         */
        public function getHighestColumn($row = null) {
            if ($row == null) {
                $colRow = $this->getHighestRowAndColumn();
                return $colRow['column'];
            }
            $columnList = [1];
            foreach ($this->getCellList() as $coord) {
                sscanf($coord, '%[A-Z]%d', $c, $r);
                if ($r != $row) {
                    continue;
                }
                $columnList[] = PHPExcel_Cell::columnIndexFromString($c);
            }
            return PHPExcel_Cell::stringFromColumnIndex(max($columnList) - 1);
        }

        /**
         * Get highest worksheet column and highest row that have cell records
         * @return array Highest column name and highest row number
         */
        public function getHighestRowAndColumn() {
            // Lookup highest column and highest row
            $col = ['A' => '1A'];
            $row = [1];
            foreach ($this->getCellList() as $coord) {
                sscanf($coord, '%[A-Z]%d', $c, $r);
                $row[$r] = $r;
                $col[$c] = strlen($c) . $c;
            }
            if (!empty($row)) {
                // Determine highest column and row
                $highestRow    = max($row);
                $highestColumn = substr(max($col), 1);
            }
            return [
                'row'    => $highestRow,
                'column' => $highestColumn
            ];
        }

        /**
         * Get highest worksheet row
         * @param   string $column             Return the highest row for the specified column,
         *                                     or the highest row of any column if no column letter is passed
         * @return  int        Highest row number
         */
        public function getHighestRow($column = null) {
            if ($column == null) {
                $colRow = $this->getHighestRowAndColumn();
                return $colRow['row'];
            }
            $rowList = [0];
            foreach ($this->getCellList() as $coord) {
                sscanf($coord, '%[A-Z]%d', $c, $r);
                if ($c != $column) {
                    continue;
                }
                $rowList[] = $r;
            }
            return max($rowList);
        }

        /**
         * Clone the cell collection
         * @param    PHPExcel_Worksheet $parent The new worksheet
         * @return    void
         */
        public function copyCellCollection(PHPExcel_Worksheet $parent) {
            $this->currentCellIsDirty;
            $this->storeData();
            $this->parent = $parent;
            if (($this->currentObject !== null) && (is_object($this->currentObject))) {
                $this->currentObject->attach($this);
            }
        }

        /**
         * Remove a row, deleting all cells in that row
         * @param string $row Row number to remove
         * @return void
         */
        public function removeRow($row) {
            foreach ($this->getCellList() as $coord) {
                sscanf($coord, '%[A-Z]%d', $c, $r);
                if ($r == $row) {
                    $this->deleteCacheData($coord);
                }
            }
        }    //    function copyCellCollection()

        /**
         * Delete a cell in cache identified by coordinate address
         * @param    string $pCoord Coordinate address of the cell to delete
         * @throws    PHPExcel_Exception
         */
        public function deleteCacheData($pCoord) {
            if ($pCoord === $this->currentObjectID && !is_null($this->currentObject)) {
                $this->currentObject->detach();
                $this->currentObjectID = $this->currentObject = null;
            }
            if (is_object($this->cellCache[$pCoord])) {
                $this->cellCache[$pCoord]->detach();
                unset($this->cellCache[$pCoord]);
            }
            $this->currentCellIsDirty = false;
        }

        /**
         * Remove a column, deleting all cells in that column
         * @param string $column Column ID to remove
         * @return void
         */
        public function removeColumn($column) {
            foreach ($this->getCellList() as $coord) {
                sscanf($coord, '%[A-Z]%d', $c, $r);
                if ($c == $column) {
                    $this->deleteCacheData($coord);
                }
            }
        }

        /**
         * Generate a unique ID for cache referencing
         * @return string Unique Reference
         */
        protected function getUniqueID() {
            if (function_exists('posix_getpid')) {
                $baseUnique = posix_getpid();
            } else {
                $baseUnique = mt_rand();
            }
            return uniqid($baseUnique, true);
        }
    }
